The present invention relates to a Schottky barrier diode and a diode array, and more particularly, it relates to a Schottky barrier diode and a diode array using a two-dimensional electron gas.
A Schottky barrier diode (SBD) is required to have a high breakdown voltage and low on resistance. In order to realize a high breakdown voltage in a conventional SBD using a silicon (Si) material, the thickness of a drift layer where a depletion layer extends in applying a backward bias voltage is increased and a carrier concentration is lowered. The drift layer is, however, a region where electrons pass in applying a forward bias voltage, and hence, the on resistance of the SBD is increased when the thickness of the drift layer is increased and the carrier concentration is lowered.
An SBD using a nitride semiconductor material such as gallium nitride (GaN) is regarded as a promising SBD with a high breakdown voltage and low on resistance. Since a nitride semiconductor material has a high breakdown field strength, a high breakdown voltage can be attained even when the thickness of a drift layer is decreased, and therefore, such an SBD attains a high breakdown voltage and low on resistance. Now, conventional SBDs using a nitride semiconductor material will be described.